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  <title>Document</title>
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  <p>请打开控制台查看</p>

  <script>
    
    function Animal(weight) {
      this.weight = weight;
    }

    Animal.prototype.breath = function() {
      console.log('体重为' + this.weight + '的动物呼吸')
    }

    var animal = new Animal(100);
    animal.breath()

    console.log('=======================')
    console.log('Animal构造函数的原型对象为：')
    console.log(Animal.prototype)

    console.log('=======================')
    console.log('animal.__proto__: ')
    console.log(animal.__proto__)

    console.log('=======================')
    console.log('Animal.prototype.constructor === Animal: ')
    console.log(Animal.prototype.constructor === Animal)

    console.log('=======================')
    console.log('animal.__proto__.constructor === Animal: ')
    console.log(animal.__proto__.constructor === Animal)
  </script>
  
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